There’s something suspiciously endearing about Jenko (Channing Tatum) in 21 Jump Street. In an early scene, the audience sees him as nothing more than a condescending jock. It’s through his budding friendship (bromance if you will) with Schmidt (Jonah Hill) that he opens himself up to be a surprisingly sympathetic character. But I’ll get to that in a second. With 21 Jump Street, I’m really unfamiliar with its source, with only the passing knowledge that Johnny Depp rose to stardom through his participation in the show. So any sort of claims as to whether directors Phil Lord and Chris Miller utilized the source material to its best effect is a little lost on me. Instead, I’m simply looking at the picture on its own terms. And it works. To a degree.

The basic premise of the film is absurd, what with cops in their mid 20s going undercover as high school students to bust a drug ring. But part of what elicits some laughs is how writer Michael Bacall (who adapted Scott Pilgrim vs. the World) acknowledges the farce. On several occasions, Bacall acknowledges the disparity between Jenko and Schmidt’s appearance (they’re meant to be brothers) and Jenko’s adult physique. These self-aware jabs are done with a sort of vigorous spirit that makes the first half of 21 Jump Street particularly effective.

But the picture falters as the action begins to ramp up in its second half. The frantic pacing recalls that of Lord and Miller’s previous directorial outing, the animated Cloudy with a Chance of Meatballs. It works fine and well for that feature, but the sheer chaos of 21 Jump Street’s second act is too jarring and lacks any sort of formal sophistication. Not that the picture calls for it, but given that it worked so well for David Gordon Green’s Pineapple Express, I had hopes that 21 Jump Street would have balanced its endearing first act qualities with a more precise filmmaking process. For a picture that was adapted from a television show, it certainly has amateurish direction on display.

But the writing is clever, integrating raunchiness with contemporary bromance comedy. I mean, it’s not particularly innovative, but it’s the sort of script that adheres to an effective comedic flow. And while Hill does an admirable job, it’s Tatum who impressed me most. His meathead persona allows him to work as a great straight man to Hill’s manic gestures. And his comic timing is surprisingly developed and on point. At one point, it would’ve probably come off as a slight to acknowledge Tatum as the best aspect of any given picture, but hey, Tatum’s the best thing in 21 Jump Street, and it’s actually a pretty good film too.